1. Field of the Invention
The present invention relates to a vehicle headlamp and, more in detail, relates to a technical field for smoothing an operation of shades in the vehicle headlamp having two shades for switching a light distribution pattern.
2. Background Art
As a vehicle headlamp, for example, there is a type in which a lamp unit having a light source is disposed within a lamp outer casing configured by a cover and a lamp housing.
Some of such lamp units are configured to include a projection lens for projecting light emitted from the light source in the forward direction, a reflector for reflecting the light emitted from the light source to a side of the projection lens, and a light distribution pattern switching mechanism disposed between the projection lens and the light source. The light distribution pattern switching mechanism may have a function of switching between two light distribution patterns, that is, a light distribution pattern for a left hand traffic and a light distribution pattern for a right hand traffic.
As the distribution pattern switching mechanism, there is proposed a type which is configured to include two shades, that is, a first shade and a second shade each formed almost in a flat plate shape for shading a part of light emitted from the light source, wherein one of the first shade and the second shade is moved vertically with respect to the other in a state that the first and second shades are disposed along the front and rear direction of a vehicle (see JP-A-2006-073224).
According to the vehicle headlamp disclosed in JP-A-2006-073224, the second shade disposed on the rear side with respect to the first shade disposed on the front side is moved vertically, whereby the light distribution pattern is changed between the light distribution pattern for the left hand traffic and the light distribution pattern for the right hand traffic.
The first shade and the second shade are closely disposed in the front and rear direction of a vehicle in order to form a clear cut line of each of the light distribution patterns.
However, according to the vehicle headlamp disclosed in JP-A-2006-073224, since the first shade and the second shade are closely disposed in the front and rear direction of a vehicle, when the second shade is moved vertically, the first shade and the second shade may rub with each other so that the smoothing operation of the light distribution pattern switching mechanism may be impeded.
In particular, it is desirable to dispose the first and second shades as close as possible in order to clarify the cut line. However, when it is intended to more clarify the cut line, the possibility of a rubbing between the first and second shades increases and so the smoothing operation of the light distribution pattern switching mechanism is more likely impeded.